Lost-motion coupling



l 192 May 0 7 R. M. GALLowAY LOST MOTION COUPLING v Filed Maron 24. 19252 Sheets-Sheet 1 v nl llllllll ll @M1221 /9 abme/1f MJ# "MMM May lo 1927R. M. GALLowAY LOST MOTION COUPLING Filed March 24, 1925 2 sheets-sheet2 nvcutoz WMM 214 @M7 @13 ation/1.043

' @mf @www Patented May 10, 1927.

UNITED STATES 1,627,964 PATENT OFFICE.

ROBERT M. GALLOWAY, OF RICHMOND, INDIANA, ASSIGNOR yTO* THE NATIONALAUTOMATIC TOOL COMPANY, OF RICHMOND. INDIANA, A CORPORATION OF IN-DIANA.

LOST-MOTION COUPLING.

Application filed March 24, 1925. Serial No. 17,968.

This invention deals with a machineelement in the nature of a lostmotion coupling which is adapted to compensate for the back-lash in areversible mechanism and may 5 be used with a gradually acceleratmgprimemover or with an abruptly acting reversing clutch. In case the lostmotion coupling 1s combined with an abruptly acting reversing clutch, ashock absorbing resilient means 1s l incorporated as an inherent part ofthe lost motion coupling. U

My invention is directed to a lost motlon coupling which will not onlycompensate for the back-lash in a reversing mechanism, but

l which will protect the tools operated by reversing mechanism againstabnormal stresses and strains. It has been recognized that more or lessback-lash must always eXlst and, in view of such fact, it is consideredpreferable to compensate for the back-lash rather than attempt tominimize the back-lash as the problem has been attacked heretofore.

The lost motion coupling preferably comprises a driving member and a.driyen member which is connected to the drivlng member by means of anumber of floating plates. The driving member, the driven member, andthe plates have projecting lugs wlnch are located to engage each otherand transmit motion from the driving member to the driven member. Theamount of lost motion in the coupling depends not only upon thethickness of the lugs on the plates and the member but also on thenumber of iioating plates provided in the coupling. Preferably theamount of -lost motion in the coupling is controlled by varying thenumber of floating plates.

The lost motion coupling may be operated either with a prime-mover,which is gradually accelerated when reversed. or with an abruptly actingreversing jaw clutch. Where an abruptly acting reversing clutch iscombined with the lost motion coupling, it is preferableto provide thecoupling with a shock-absorbing resilient means. When a "n prime-mover,such as a reversing motor, is

combined with the coupling, the gradual acceleration of the motor in a.reverse direction protects the lost motion coupling and the parts joinedtoit against abrupt shocks.

The lost motion coupling not only serves to effect the correctcorrelation between the reverse movements of the parts in a poweroperated reversing mechanism by compensating for the back-lash, but alsoserves to protect the tool or tools operated by the mechanism againstcertain abnormal stress and strains. The pause effected at the point ofreversal of the mechanism permits the accumulated stress and strains todissipate before the reverse movement of the mechanism is started.

Unc practical use of the present lost-motion coupling is disclosed in myco-pending application Serial Number 17,969 filed March 24, 1925.

Other objects and advantages will be in part indicated in the followingdescription and in part rendered apparent therefrom in connection withthe annexed drawings.

To enable others skilled in the art so fully to apprehend the underlyingfeatures hereof that they may embody the same in the various wayscontemplated by this invention, drawings depicting a preferred typicalconstruction have been annexed as a part of thi-s disclosure and, insuch drawings, like characters of reference denote corresponding partsthroughout all the views, of which In the accompanying drawings, Figure1 is an elevational view partially in section of a lost motion couplingconstructed in accord ance with my invention. Fig. 2 is a sectional viewalong line 22 of Fig. 3. Fig. 3 is a sectional View along the line 3 3of Fig. 2. Fig. 4 is an elevational view partially in section of a lostmotion connection having shock absorbing elements. Fig. 5 is a plan viewpartially in section of the connection shown in Fig. 4.

Referring to Figs. 1, 2 and 3 of the drawings a lost motion connectionis illustrated which is adapted to connect a driving shaft 2 with adriven shaft 1. The lost motion connection comprises a driven member orsleeve plate 3 which is tixedly mounted on a driven shaft 1.Preferably,- suitable keys 4 and n. pin 5 are provided for securing theyplate to the shaft 1. The plate 3 is provided with a hub portion 6 uponwhich are mountcd bushings 7 and 8. The bushings 7 and 8 respectivelycarry two fioating plates 9 and 10. Adjacent to the fioating plate 9 ismounted a driving member 11 which is secured to the driving shaft 2 by asuitable key 12. The fioating plates 9 and- 10 and the disk Aportion ofthe driving member 11 are surrounded by a casing or housing 13 which issecured to the sleeve plate 3 by means of a jecting ing 15 in a housing13 is provided for inserting lubricating material within the housing.

The sleeve plate 3 is provided with a projecting lug 16 which is adaptedto be engaged by a projecting lug 17 on the floatinfv plate '10. Thefloating plate 10 is provided with a second projecting lug 18 which ismounted in the path of movement of a projecting luO 19 on the floatingplate 9. The floating p'late 9 is provided with a'second projecting lug2() which is positioned 'in the path of movement of a lug 21 projectingrom the driving member 11.

Referring toliig. 1 of 'the drawings, mo`

tion is directly transmitted from the driving shaft 2 to the drivenshaft 1 when the lugs 21 to 16 inclusive are positioned as indicated onthe drawings and the shaft 2 is rotated in a direction of the arrow a.Upon rotation of the driving shaft 2 in a reverse direction, apredetermined lost lnotion'is provided before rot-ation of the drivenshaft 1 is effected. The lost motion produced upon reversing thedirection of rotation of the driving shaft 2 depends upon the number offloating plates provided in the connection and upon the width of theprojecting lugs on the fioating platesand on the driving and drivenmembers. The rotation of the shaft 2 and the driving member 11 in areverse direction effects a complete rotation less the thickness of theprojecting lugs 21 and 20 before any movement of the floating plate 9 iseffected. When the lug 21 engages the opposite side of the lug 20, thefloating plate 9 is rotated through a complete rotation less thethickness of the projecting lugs 19 and 18. When the lug 19 engages theopposite side of the projecting lug 18, the floatmg plate 10 is rotatedthrough a complete rotation less the thickness of the projecting luus 17and 16. 'When the prolug 1 engages the opposite side of the projectinglug 16 the driving shaft 2 is directly connected to the driven shaft- 1.

The amount of lost motion produced by a connection such as shown inFigs. 1, 2 and 3 is equal to three rotations of the driving shaft 2 lessthe thickness of the projecting lugs. The amount of lost motion may bevaried by changing the thickness of the lugs and by varying the numberof the floating plates. Preferably, the lost motion is con` trolled byvarying the number of floating plates provided in the connection.

The floating plates 9 and 10 are preferably provided with holes 25 and26 for supplying lubricating material to the bearingy surfaces on thebushings 7 and 8 which sup'- port the floating plates. Preferably,abushing 27 is mounted on the reduced portion 28 of the driven shaft 1for engaging the hub l sorbing means must be provided between thevvarious projecting lugs on the plates in the connection.

In Figs. 4 and 5 is disclosed lost motion connection which is suitablefor operation with a quick acting reversingmechanism such as an ordinaryso-called7 jaw clutch.

'The connection shown in Figs. 4 and 5 comprise a driven member 30 whichis fixedly mounted on a driven shaft 31. Preferably, the driven member30 is secured to the shaft' 31 by a key 32 and a pin 33. A hub portion34 on the driven member 3() carries a bushing 35. The bushing 35supports a floating plate 36 which carries two floating rings 37 and 38.A ydriving member 39, which is mounted on a driving shaft 40, ispositioned adjacent to the floating plate 36 which is adapted to beoperated by the member 39. A lug 41, which projects from the sleevemember 30, is positioned in the path of movement of a lug 42 on thefloating plate 36.

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A second projecting lug 43 on the floating plate 36 is positioned4 iithe path of movement of a lug 44 on the driving member 39. Two spring.members 45 and 46, which are shown in Fig. 5 of the drawings, arepositioned on opposite sides of the projecting lug 43 on the floatingplate.' Spring members, similar to the spring members 45 and 46, arepositioned on opposite sides of the lug 42 which project from thefloating-plate. The fioating-ring 38 serves to hold the two springmembers 45 and 46 in position to be engaged by the lugs 43 and 44 andthe oating ring 37 serves to hold .the two spring members associatedwith the lugs 41 and 42 in position to be engaged by ,such lugs. Acasing or housing 47 is provided for the coupling and preferably issecured to the sleeve plate 3() by means of a screw 48.

Assuming the driving shaft 40 to be rotating in a clockwise direction,the lug 44 projecting from the driving member 39 compresses the spring45 between it and the lug mechanism. `Upon reversing the direction ofbe,

to the spring member 46 as shown in Fig.

5. The counter-clockwise rotation of the driving shaft compresses thespring member 46 between it and the lug 43 projecting from the plate 36.It will be notedhowever that before the lug 44 engages the spring member46, the shaft 40. and the driving member 39 have' made one revolutionless the thickness of the lugs 43 and 44 and the length of the spring46. The compressing of the spring 46 serves to cushion the shockiproduced by the abrupt reversing of the shaft 40. 'The plate 36 isrotated through one revolution less the thickness of the lugs 41 and 42and the length of one of the spring members before effecting 'anymovement of the driven member 30. A fixed and rigid connectionbetvveen'the` shafts 40 and 31 is not effected until completecompression of the springs which are'located between the lugs on thedriving and driven members and on the fioating plate.

The herein disclosed coupling is applicable to a great number of.mechanisms and serves amon other purposes not only to compensate orlost motion but also serves, as heretofore set forth, to protect toolsoperated by reversing mechanisms against certain abnormal stresses andstrains. The lost motion coupling is particularly applicable toreversing mechanisms which have movement in accordance with a helix.However the lost motion coupling serves to lengthen the -life of cuttingtools which are used on reversing mechanisms.

Without further analysis, the foregoing will so fully reveal the gist ofthis invention that others can, by applying current knowledge, readilyadapt it for various utilizations by retaining one or more of thefeatures that, from the standpoint of the prior art, fairly constituteessential characteristics of either the generic or specific aspects ofthis invention and, therefore, such adaptations should and are intendedto be, comprehended within the meaning and range of equivalency of thefollowing claims.

Having thus revealed this invention, I claim as new and desire to securethe following combinations and elements, or equivalents thereof, byLetters Patent of the United States l. In a lost motion coupling, thecombination comprising a driving member; a driven member adapted to beoperated by said driving member; a floating plate'positioned between thedriving and driven members; coacting lugs projecting from the sides ofsaid members and the oating plate for driving the driven member from thedriving member and for producing a predetermined lost motion u )onreversing direction of rotation of the driving member; resilient memberspositioned between said lugs to prevent shock upon abruptly reversingthe driving member, said resilient members extending only through aportion of the total circular distances between engaging lugs; andfloating rings mounted on said f ioating plate for holding saidresilient'menibers in position to be engaged by said lugs.

2. A lost motion coupling for driving and driven shafts comprising adisk secured to the driving shaft; a disk secured to the driven shafts;a lug projecting from each of said disks; a plurality of disks rotatablyjournaled intermediate said driving and driven disks and each providedwith oppositely extending lugs,V the lugs on the intermediate disksbeing adapted, by relative rotation, to engage each other and the lugson the driving and driven disks; a casing member secured to the disk onone of said shafts and together with said disk forming a substantiallyoil-tight housing for all of said disks; and means permitting theinsertion of lubricating material in said housing.

In witness whereof, I have hereunto subscribed niy name.

ROBERT M. GALLOWAY.

